Coincidence-telemeter.



PATENTED SEPT. 1 i, 1 906.

' A. KONIG; H

co mmmcn TELEMBTER.

APPLIUATIdlI FILED APR. 9, 1906.

c a o n mrnn STATES, PATENT OFFICE;

ALBERT KONIG, or JENA, GERMANY, ASSIGNOR TO THE FIRM or CARL- ZEISS, OF JENAYGERMANY, j- OOINOI DEN C E -TE Z LE METER.

m.'sao,ecs.

I Specification of Letters Patent.

Patented Sept. 11, 1906.

Application tiled A rils; 1906. Serial No. 310,782-

To all whom it may concern:

Be it known that I, ALBERT Kome, doctor of philoso by, a citizen of the German Empire, resi mg at Carl Zeiss strasse, Jena, in the Grand Duchy of Saxe-Weimar, Germany, have invented a new and useful Coincidence-- Telemeter, of which the following .is a specification.

'Thei'nventioh consists in an improvement in coincidence-telemeters+that is, in telem= eters designed for individual observation 'with two telescopes (but one ocular common to both) arranged on either a horizontal or vertical base-line, and with a micrometermeasuring' appliance, by means of which the system of pencils of rays of one-telescope is deviated in the sightingplane so as to move one telescope image in the direction of the i the instrument or 5 I mg-prism, and to win base-line until the points of the two telescope images in which the object'- oint is reproduced whose distance is to e determined lie in the same perpendicular to the base-line, dinarilybeing adjusted so that the distance between both image-points in the perpendicular referred to vanishestlhat is, the two image-points become coincient.

The invention incidence-telemeters whose objectives have their focilying in the same point in a cement film, which unites the two parts of a separat- 'ch, in the same lane, the separating-surface of this prism a joins, whose effect already known is that the two images presented to the observer by the common ocular do not. overlap, but are contiguous. With telemeters ofthis kind, as with coincidence-telemeters in general, the essential condition for an exact measurement'is. the invariability of the relative situation of both images projected by the-objectives with a given position of the measuring appliance. Again, such invariability of the situation of the images rests, in general, upon the invariability of the relative'position of those optical parts through which the pencils pass before the formation of the images.

The present invention consists in such formation and arrangement of this optical system which reduce the number ofits individual parts, and on that account also the probabihty of the position of 'a part becoming de-- ranged. This aim is substantially attained by -arranging the entrance-surfaces of the mg prisms,

admitted into that flected but once by reflection particularly relates to co-' separatingrism perpendic ar to t e base-line. The reflectwhich; were hitherto arranged between the separating-prism and the'ob jelctive prism, are then dispensed with, for t e s the o jective prism or the objective in the direction of the base-line can beimmediately prism proper to it. The se arranged as above,.attains t mation and that occupying when the axis of one system c simplest forthe least space and that of the other deflected not at all before they intersect in the cement film. The objectiverisms are then, however, unequally located orward in the sighting-plane, 'renderin the construction of the casmg diflicult. romthis consideration it is preferable to substi-f I 75 art of tute a prism having two deflections in opposite directions for the undeflecting the separatin -prism. The principal of the axes o? the two systems, each parallel to the base-line, are thus brought into alinement, and the objective prisms .lie symmetrically.

In order to fully realize the advantageaccruing to the invention-'5. e., the comparative invariability of the relative position of the imagesthe complex objective 'rism engtlis arallel to each other and,

stem of pencils, which emerges frompart of the separatingarating-prism,

of pencils is desystems ordinarily em loyed in this kind of coincidence-telemeters ould beavoided. Op-

.tical square prisms adapt themselves best as the ob ective prisms, and they have alread been often employed in telemeters for suc pu' oses. The general arrangement, as de-- scri ed, of two objective prisms and two prisms cemented together to form a separatmg-prism despite its great simplicity makes it b no means necessary to employ a terrestria ocular to rerect the images projected inverted by the objectives. On the contrary, a com lete image erection is also effected in the rig t telescope as well as the left by means of the four above-mentioned prisms if a roof orv ridge shaped reflecting-surface, well known as an erecting. system, be used. instead of a sim 1e reflecting-surface and for the rest care lie. taken that the number of simple reflecting-surfaces encountered b the effectual pencils in their passage through the instrument'be an even one.

In the annexed drawings, Figure 1 is a per:

prism system. 1 second modified four-prism system.

spectlvc view of a scheme of four prisms, formln g, according to the invention, the essential optical skeleton of the new telemeter. Fig 2 is a similar view of a modified four Fig. 3 is a similar view of a Fig. 4 is a sectional plan of a telemeter with the pri in system set out according to Fig. 2.

ln'all three examples of four-prism systel 18 the deflecting separating-surface adjo ning the cement film of the separatingprism isrendered recognizable by shading. The separating-surface lies perpendicularly to the sighting-plane, and reflection occurs on both sides, for which purpose it is silvered. It surrounds the cement film in the case of Fig. 1, and it lies below this film in Fig. 2 and above'in Fig. 3. The point of intersection a of the axes of'the systems, in which lie the focal pointsof both objectives, falls in the cee ment film in Fig. 1 in its middle, in its boundary-line in both the other examples. The directions of the axes of-both systems are continued beyond theintersecting point a until at least the exit-surface of the separating- .prism. Beyond the point a each axis represents a com ound system consisting of the direct unde ected pencils of onesystem and the reflected pencils of the other system.

Both parts do not correspond to one another,

but are complementary, giving images which are conti uous and form together the total image. n the cases of Figs. 1 and 2, where the cement film and the silvered surface lie at forty-five degrees to the base-line, the axes aredirected one parallel and the other per- "pendicular to the base-line and emerge from perpendicular surfaces of the separatingrism without further deflection. In both these cases, therefore, can either the one or the other of the two compound systems of pencils emerging from the separating-prism be used for observation.-viz., either the .one emerging perpendicular to the base-line whose axis is indicated by a single arrowhead or the one emerging parallel to the basc line whose axis is denoted by a double arrowhead- Were the compound system of pencils whose axis emerges perpendicular to the base-line chosen a direct vision ocular can be used, while the compound.

sitates the employment of an angled vision ocular. In the case of Fig. 3 the se aratingsurface has other inclination than fbrty-five degrees to'the base-line, and while theone 'axisthat denoted by the double arrowhead-passes through the separating-prism arallel to the base-line and emerges unde ected from the perpendicular exit-surface, the direction of the axis denoted with a sinle arrow-head deviates in this instance om the perpendicular to the baseline, and this deviation becomes greater still upon emergence from the exit-surface of the sepasystem whose axis emerges parallel to the base-line neces rating-prism, as this surface is parallel to the base-line. In system denoted by a double arrow-head can conveniently be used,- and that one again by means of an angled ocular.

, Besides the different forms of the separating-prism, (resulting from the different inclinations. of the separating-surface to the base-line,) that according to Figs. 1 and 2 on the one hand and that according to Fig. 3 on the other, there is still, mainly, a. second ing-prism according to Fig. 1 on the one hand and the other. While in all three cases-the component I) gives the axis of the left system the direction toward the point a by a single defiection by reflection, the component, 0 in Fig. 1 conveys the axis of the right system unde- Fig. v2 and c in .Fig. 3, on the contrary, dcflects the axis twice in opposite directions previously amples represented as square prisms.

The erection of both imagesis only effected 'in the first two prism arrangements. For this purpose the ridge reflecting-surface is 1 to the component b at f and to Prandls optical venient to use in the arrangement of Fig. 3. If it berequired to use in Figs. 1 and 2 the like compound system necessitating an angled ocular, then the angled form of the ocular is supplied by a simple reflectingprism whose reflecting-surface supplements eration to n'iake up an even number of such.

With the telemeter according to Fig. 4 an astronomical ocular is used, utilizing the compound system whose axis lies perpendicular to the base-line. The two objectives 7c and-Z are cemented to the Prandl prisms cl and e. The measuring appliance is operative through deflection of the right system of pencils. The indicator m and the scale n, here half erected, are visible through the window 0. The scale is rigidly connected with the carrier of the deflecting-prism g, which can be moved in a direction parallel to the axis of the system of pencils in the sliding guide 1. The latter is connected with the rack s, which, together with the pinion t, governed from the outside of the casing a by the milled head. v, serves to give the above mentioned movement.

.this case only the compound such difference existingbetween the separatflected to the point'a, the component c in line and, according as above, is the most conthe simple reflecting-surfaces already in opthat according to Figs. 2 and 3 on The objective'prisms d and e are in all ex- ,What I claim as my invention, and desire to secure by Letters Patent, is

1. Coincidenee-telemeter which comprises objectives in coincidence, and lying in the same plane as and adjoining to the separating-surface, the entrance-surfaces of the separatingprism being arranged parallel to one another line: j

2. Coineidence-telemeter which comprises two objectives and a separating-prism carrying a separating-surface and composed of two cpmponentscemented together, the cement film containing the focal points of both objectives in coincidence, and lying in the same plane as and adjoining to the separating-surface, the entrance-surfaces of the separating-prism being arranged parallel to one another and perpendicular to thebaseline, the said separating-prism presenting one reflecting-surface to the axis of. one of and perpendicular tothe base the two systems of pencils before-the axis passes through the cement film.

3. Coincidence-telemeter which comprises two objectives and a separ'ating-prismcarry- 1ng a separating-surface and composedof two components cemented, together, the ce'- ment film containing the focal points of both objectives in coincidence, and lying in the same plane as and adjoining to the separating-surface, the entrance-surfaces of the separating-prism being arranged parallel to one another and perpendicular to the base line, the said separating-prism presenting one reflecting-surface to the axis of one system of pencils, and two reflecting-surfaces successively to the axis of the other system of pencils, before the axes pass through the cement, film.

In testimony whereof I havename to this specification in two subscribing Witnesses.

ALBERT KONIG. 1

signed my the presence of Witnesses PAUL Knt'ienn, Fnrrz SANDER. 

